Minimally invasive surgical techniques have been adopted worldwide to replace conventional surgical procedures that reduce the amount of extraneous tissue that may be damaged during surgical or diagnostic procedures, thereby reducing the patient recovery time, discomfort, prolonged hospital stays and particularly deleterious side effects. Typically, medical robotic systems require a close coupling between the robotic manipulators and the surgical instrument defining the end effectors configured to be delivered through a small percutaneous penetration in a body cavity.
Heretofore, the coupling mechanism in surgical robotic systems comprises a driving unit to transfer the controlling motions from the functional end of the robotic arm to the detachably attached surgical instrument and to make the instrument separately sterlizable for use during the course of performing the surgery. Furthermore, the coupling enhances significantly the safety, accuracy, dexterity and speed of minimally invasive and other robotically enhanced procedures. However, in the most commonly employed configurations, the coupling mechanism has a finite range of motion owing to the arrangement of components on its either side that are configured for transferring electro mechanical signals from the robotic arm to the surgical instrument. The limitation in motion adversely hampers the free movement of the coupling arrangement, so necessitated during the surgery. Now, in order to compensate for the undue loss in free motion of the coupling arrangement, the robotic arm may have to traverse an undesirable broader course that may enhance probability of potential conflict between said arms.
Furthermore, necessitating the presence of driving unit to actualize the motion of the surgical instrument is ostensibly cumbersome, as it creates an additional dependency of the surgical instrument upon the driving unit to be operable, which is uncalled-for, especially in a scenario where the attempt is to make the system flexible and modular to minimize the floor occupancy area, or alternatively enhance the robotic arm mobility area with minimum risk of collision or conflict with other robotic arms.
The robotically assisted medical systems utilize a sterile barrier to separate the non sterile robotic arm from the mandatorily sterile surgical instrument operating environment. This sterile barrier often includes a sterile plastic drape that envelops the robotic arm and a sterile adaptor that operably engages with a sterile surgical instrument in a sterile field and non sterile manipulator arm, and includes a flexing drape interface to retain a drape section therebetween such that while the torque and other force feedbacks is received as an input from both the surgical instrument as well as the robotic arm, the sterile barrier is maintained between the sterile surgical instrument and the non-sterile robotic system. Also, the portion of same sterile drape shields the cannula adaptor effectively such that the non exposed portion of adaptor remains sterile.
However, many new challenges are posed with the present aforesaid technique. For example, the drape interface if not properly aligned or dressed over the instrument supporting assembly, instrument or cannula adaptors, may get entangled, and interfere with the motion of the surgical instrument. There always remains a concern of unfolding drape over the cannula adaptor and forming a sag in drape at the cannula mount area, still folding the excess drape back enough to closely fit the shape of the cannula holding assembly and preserve sterility. Additionally, the sterile adaptors disadvantageously involve complex assembly of various intricate components for coupling with corresponding complementary arrangements on the manipulator arm on one side and the surgical instruments on the other, thereby making the whole process costly and cumbersome.
In the light of aforementioned challenges, what is needed, therefore, is a robotically assisted or tele-robotic assembly that allows easy detachability of surgical instruments or diagnostic devices during performance of surgery without breaking the sterile barrier while reducing the complexity of any sterile adaptor. Moreover, from a cost perspective, it would be preferable to have sterlizable modular interface, thus requiring the system to be simpler so as to allow unobstructed movement of the surgical instrument for enhanced precision and control.